If you are looking for something advanced, you should check books written by C. J. Date. For example, his "An Introduction to Database Systems" considered as one of the best book on database theory.
However he insists on living in his relational purist fantasy land without nulls or outer joins or other pragmatic things that people who use databases to get real work done rely on every day.
After dropping btrfs support some time ago they started developing their own next-gen file system based on LVM and XFS.
It is now available for technology preview on Fedora 28.
Actually, it is quite opposite. ZFS is a copy-on-write filesystem - if you do write in the middle of your file the datablock gets moved to a new place on your disk.
For typical database load your db files get more and more fragmented with time.
On my previous job we had to manage thousands of customer domains, including annual renewal.
This was very tedious task, so I wrote a Perl script, scraping WHOIS and DNS data for all domains listed on our DNS servers. Based on this data every domain was assigned a status, such as "Ok", "misconfigured", "about to expire", "points to foreign DNS server" or "points to foreign Web server". This script was scheduled to run every other day and sent CSV report (full and diff from previous run) to a person responsible for domain renewal.
Needless to say, our support specialists were very happy with this improvement.
Interestingly, Wikipedia translates "Nu, pogodi" as "Well, you just wait".
Actually, this phrase is a threat and should be translated something like "I will get you".
In Russia we served HTTP traffic on non-standard ports, such as 8100, 8101, 8102 in addition to default 80. It was very common in 90s. Can anyone guess, why?
To solve the problem with non-US character-encoding.
Web browsers of 90s were notoriously bad with client-side encoding. The only way to show content properly for all available clients was server-side recoding and different HTTP ports were used to serve content with different encoding - ISO, DOS, Windows and KOI. Each web-page had a set of links, usually in top-right corner, labeled as "ISO", "DOS", "Win" and "KOI" which transferred you to corresponding HTTP port.
I was surprised to find Web of Trust addon ( https://addons.mozilla.org/en-US/firefox/addon/wot-safe-brow... ) in top 10. From my past experience https://mywot.com is nothing more than a scam. Their ratings are not reliable and should not be trusted by anyone.
For example, our business website was rated with "Child safety: Very poor" and there is nothing we could do about it.
You should not judge about all Russians by those tourists.
Unfortunately, during last 20 years in Russia, being such scoundrel and scumbag, you have pretty high chance to earn good money. Even in Russia nobody likes these (very small number of) people and wants to travel to the resort where there are no "damned Russian tourists". :-)
